Preparation of low defect density of iii-v on si for device fabrication

ABSTRACT

A method of forming a semiconducting material includes depositing a graded buffer on a substrate to form a graded layer of an indium (In) containing III-V material, the In containing III-V material being indium-gallium-arsenic (InGaAs) or indium-aluminum-arsenic (InAlAs) and comprising In in an increasing atomic gradient up to 35 atomic % (at. %) based on total atomic weight of InGa or InAl; and forming a layer of InGaAs on the graded layer, the layer of InGaAs comprising about 25 to about 100 at. % In based on total atomic weight of InGa.

DOMESTIC PRIORITY

This application is a continuation of and claims priority from U.S.patent application Ser. No. 14/697,953, filed on Apr. 28, 2015, entitled“PREPARATION OF LOW DEFECT DENSITY OF III-V ON SI FOR DEVICEFABRICATION,” the entire contents of which are incorporated herein byreference.

BACKGROUND

The present disclosure generally relates to semiconductor devices, andmore specifically, to semiconducting materials on silicon substrates.

Semiconducting III-V compounds and materials, e.g.,indium-gallium-arsenic (InGaAs) and indium-gallium-antimony (InGaSb), intransistor channel devices have low band gaps and high carrier mobilityproperties. However, integrating the III-V materials on silicon (Si) orgermanium (Ge) substrates is challenging. Generally, conventional III-Vmaterials on Si substrates need a relatively thick buffer layer toachieve an acceptable defect density. Defects, such as stacking faultsand dislocations can occur with high defect densities due the latticemismatch between the III-V and the substrate.

Thick buffer layers, including graded buffer layers, can take extensivetime to form and may not provide the desired defect density. Forexample, a thick graded buffer layer to integrate a III-V material on Simay only achieve a defect density of about 2×10⁹ defects/centimeter²(defects/cm²), which is demonstrated by Intel Corp.

SUMMARY

In one embodiment of the present disclosure, a method of forming asemiconducting material includes depositing a graded buffer on asubstrate to form a graded layer of an indium (In) containing III-Vmaterial, the In containing III-V material being indium-gallium-arsenic(InGaAs) or indium-aluminum-arsenic (InAlAs) and comprising In in anincreasing atomic gradient up to 35 atomic % (at. %) based on totalatomic weight of InGa or InAl; and forming a layer of InGaAs on thegraded layer, the layer of InGaAs comprising about 25 to about 100 at. %In based on total atomic weight of InGa.

In another embodiment, a method of forming a semiconducting materialincludes forming a high aluminum content III-V material layer on asubstrate, the III-V material comprising at least one III element and aV element, the at leasing one III element comprising Al and beingpresent in an amount of least 50 at. % based on total atomic weight ofthe at least one III element; depositing a graded buffer on the highaluminum content III-V material layer to form a graded layer of an Incontaining III-V material, the In containing III-V material being InGaAsor InAlAs and comprising In in an increasing atomic gradient up to 35at. % based on total atomic weight of InGa or InAl; forming a layer ofInGaAs on the graded layer, the layer of InGaAs comprising about 25 toabout 100 at. % In based on total atomic weight of InGa; and oxidizingthe high aluminum content III-V material layer to form AlO.

Yet, in another embodiment, a semiconducting material includes asubstrate; a high aluminum content III-V material layer disposed on thesubstrate, the III-V material layer comprising at least one III elementand a V element, the at leasing one III element comprising Al and beingpresent in an amount of least 50 at. % based on total atomic weight ofthe at least one III element; a graded layer of an In containing III-Vmaterial disposed on the high aluminum content III-V material layer, theIn containing III-V material being InGaAs or InAlAs and comprising In inan increasing atomic gradient up to 35 at. % based on total atomicweight of InGa or InAl; and a InGaAs layer disposed on the graded layer,the InGaAs layer comprising about 25 to about 100 at. % In based ontotal atomic weight of InGa.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter which is regarded as the invention is particularlypointed out and distinctly claimed in the claims at the conclusion ofthe specification. The forgoing and other features, and advantages ofthe invention are apparent from the following detailed description takenin conjunction with the accompanying drawings in which:

FIG. 1A illustrates a cross-sectional side view of high aluminum contentIII-V layer disposed on a substrate;

FIG. 1B illustrates a cross-sectional side view of a graded layerdisposed on the high aluminum content III-V layer of FIG. 1A.

FIG. 1C illustrates a cross-sectional side view of anindium-gallium-arsenic layer (InGaAs) disposed on the graded layer ofFIG. 1B;

FIG. 2 illustrates a cross-sectional side view of a semiconductingmaterial having a partially oxidized high aluminum content III-Vmaterial layer according to an exemplary embodiment;

FIG. 3 illustrates a cross-sectional side view of a semiconductingmaterial having a high aluminum content III-V material with partialoxidation along lateral edges of the high aluminum content III-Vmaterial layer;

FIG. 4 illustrates a cross-sectional side view of a semiconductingmaterial having a high aluminum content III-V material layer that issubstantially fully oxidized to aluminum oxide (AlO);

FIG. 5A is a transmission electron micrograph (TEM) image of across-sectional view of a graded layer of InGaAs having an increasing Inatomic gradient up to 20%;

FIG. 5B is a TEM image of a cross-sectional view of a graded layer ofInGaAs having an increasing atomic gradient of In up to 20%;

FIG. 6A is a TEM image of plan-view of an InGaAs layer;

FIG. 6B is an atomic force microscopic (AFM) image of an InGaAs layerdisposed on Si;

FIG. 7A is a scanning electron microscope (SEM) image showing oxidationof an AlAs layer to AlO;

FIG. 7B is a SEM image showing an AlAs layer that is substantially fullyoxidized to AlO;

FIG. 8A illustrates linear current as a function of voltage in asemiconducting materials having a partially oxidized AlAs layer and anunoxidized AlAs layer; and

FIG. 8B illustrates a log scale graph of FIG. 8A.

DETAILED DESCRIPTION

Disclosed herein are semiconducting materials and methods of makingthereof. Semiconducting materials include III-V materials on asubstrate. In some embodiments, the III-V material is an In containingIII-V material, such as InGaAs or InAlAs. The substrate can be, forexample, a Ge/Si substrate, or a substrate with Ge deposited on Si. Ahigh degree of lattice mismatch between Ge and Si can induce defectsinside the deposited Ge portion of the substrate. The present disclosuretherefore provides for integration of a III-V material on a Si substratewith desirable defect density, for example, less than 2×10⁷ defects/cm².

The methods also can be used to apply a III-V material to a Ge substratedirectly. Because the starting defect density of Ge is relatively low,for example, less than 1×10³ defects/cm², the final III-V integratedmaterial (e.g., InGaAs) on the Ge substrate can provide a desirabledefect density, for example, about 1×10⁶ defects/cm².

In one embodiment, optionally, a high aluminum content III-V materiallayer is formed on the substrate before integrating the III-V material,which serves as a layer for later oxidation. Graded layers of an indium(In) containing III-V material is formed on the high aluminum contentIII-V material layer. In an exemplary embodiment, a portion of thegraded layer includes (In_(0.35)Ga_(0.65)As). A thin layer of InGaAshaving about 25 to about 100 at. % In is then formed on the gradedlayer. The resulting semiconducting materials have low defect densities,for example, less than 2×10⁷ defects/cm², and are substantially stackingfault free.

The following definitions and abbreviations are to be used for theinterpretation of the claims and the specification. As used herein, theterms “comprises,” “comprising,” “includes,” “including,” “has,”“having,” “contains” or “containing,” or any other variation thereof,are intended to cover a non-exclusive inclusion. For example, acomposition, a mixture, process, method, article, or apparatus thatcomprises a list of elements is not necessarily limited to only thoseelements but can include other elements not expressly listed or inherentto such composition, mixture, process, method, article, or apparatus.

As used herein, the articles “a” and “an” preceding an element orcomponent are intended to be nonrestrictive regarding the number ofinstances (i.e. occurrences) of the element or component. Therefore, “a”or “an” should be read to include one or at least one, and the singularword form of the element or component also includes the plural unlessthe number is obviously meant to be singular.

As used herein, the terms “invention” or “present invention” arenon-limiting terms and not intended to refer to any single aspect of theparticular invention but encompass all possible aspects as described inthe specification and the claims.

As used herein, the term “about” modifying the quantity of aningredient, component, or reactant of the invention employed refers tovariation in the numerical quantity that can occur, for example, throughtypical measuring and liquid handling procedures used for makingconcentrates or solutions. Furthermore, variation can occur frominadvertent error in measuring procedures, differences in themanufacture, source, or purity of the ingredients employed to make thecompositions or carry out the methods, and the like. In one aspect, theterm “about” means within 10% of the reported numerical value. Inanother aspect, the term “about” means within 5% of the reportednumerical value. Yet, in another aspect, the term “about” means within10, 9, 8, 7, 6, 5, 4, 3, 2, or 1% of the reported numerical value.

As used herein, the term “III-V material” means a material or compoundincluding at least one III element and at least one V element.

As used herein, the term “III element” means aluminum (Al), boron (B),gallium (Ga), indium (In), or any combination thereof.

As used herein, the term “V element” means nitrogen (N), phosphorous(P), arsenic (As), antimony (Sb), or any combination thereof.

Referring now to the figures, FIG. 1A illustrates a cross-sectional sideview of a semiconducting material 100 according to an exemplaryembodiment. Optionally, a high aluminum content III-V material layer 120is disposed on a substrate 110. The high aluminum content III-V materiallayer 120 can be, for example, AlAs. The high aluminum content III-Vmaterial layer can serve as an oxidation layer, as discussed below. Insome embodiments, the semiconducting material 100 does not include ahigh aluminum content III-V material layer.

The substrate 110 includes any suitable substrate material. Non-limitingexamples of suitable substrate materials include p-type materials,n-type materials, neutral-type materials, silicon, germanium, galliumsilicon, germanium arsenide, silicon germanium, silicon-on-insulator, orany combination thereof.

In an exemplary embodiment, the substrate 110 is a Ge/Si substrate. Geis deposited on an off-cut Si wafer before the below III-V materials.One 1 micrometer (μm) Ge on a 6 degree off-cut Si wafer can be used. TheGe/Si substrate has a defect density of about 1×10⁷ to 1×10⁹defects/cm².

The thickness of the substrate 110 is not intended to be limited. In oneembodiment, the thickness of the substrate 110 is in a range from about200 micrometers (μm) to about 1,000 μm. In another embodiment, thethickness of the substrate 110 is in a range from about 600 μm to about800 μm. Yet, in another embodiment, the thickness of the substrate 110is about or in any range from about 200, 300, 400, 500, 600, 700, 800,900, and 1,000 μm.

The beginning substrate 110 has a defect density (DD) in a range fromabout 1×10² to about 1×10⁹ defects/cm². In some embodiments, thesubstrate has a defect density of less than 2×10⁸ defects/cm².

The optional high aluminum content III-V material layer 120 is formed onthe substrate 110 from a III-V material. The III-V material includes atleast one III element and a V element. At least one of the one or moreIII elements is Al. Al is present in an amount of least 50 at. % basedon total atomic weight of the one or more III elements. In otherembodiments, Al is present in an amount of at least 55, at least 60, atleast 65, at least 70, at least 75, at least 80, at least 85, at least85, at least 90, at least 95, or at least 100 at. % based on totalatomic weight of the one or more III elements. For example, Al

In one example, the high aluminum content III-V material layer 120includes aluminum (Al) (a III element) and arsenic (As) (a V element)and is AlAs. AlAs includes 100 at. % Al based on total atomic weight ofthe III elements.

The high aluminum content III-V material layer 120 is formed on thesubstrate 110 by, for example, metal organic chemical vapor deposition,molecular beam epitaxy, photolithography, or other such suitableprocesses.

The thickness of the high aluminum content III-V material layer 120 isnot intended to be limited. In one embodiment, the high aluminum contentIII-V material layer 120 has a thickness in a range from about 1 nm toabout 1 μm. In other embodiments, the high aluminum content III-Vmaterial layer 120 has a thickness in a range from about 1 nm to about10 nm. In another embodiment, the high aluminum content III-V materiallayer 120 has a thickness about or in any range from about 1 nm, 10 nm,50 nm, 100 nm, 250 nm, 500 nm, 750 nm, and 1 μm.

FIG. 1B illustrates a cross-sectional side view of a graded layer 130disposed onto the optional high aluminum content III-V material layer120 of FIG. 1A. Depositing a graded buffer on the high aluminum contentIII-V material layer 120 forms the graded layer 130. The graded layer130 can be deposited, for example, by metal organic chemical vapordeposition (MOCVD) or molecular beam epitaxy (MBE). In one embodiment,the graded layer 130 is formed directly on the substrate 110 (notshown).

The optional high aluminum content III-V material layer 120 can serve asan oxidation layer. Because the oxidation rate depends on Al content, atleast 50 at. % Al is used. Using a layer of AlAs, which is then oxidizedto AlO, reduces leakage to the substrate.

As discussed above, the high aluminum content III-V material layer 120can be any III-V material that includes Al as a III element component inan amount of at least 50 at. %. For example, the high aluminum contentIII-V material can be Al-V, wherein V is any V element(s), for example,nitrogen (N), phosphorous (P), arsenic (As), antimony (Sb), or anycombination thereof. Al is present as the III element alone or incombination with other III elements, for example, boron (B), gallium(Ga), indium (In), or any combination thereof. The high aluminum contentIII-V material layer 120 can include Al as the III element component inan amount about or in any range from about 50, 55, 60, 65, 70, 75, 80,85, 90, 95, and 100 at. %.

According to an exemplary embodiment, the high aluminum content III-Vmaterial layer 120 is Al0_(.95)Ga_(0.05)As, wherein the III elementportion is 95 at. % Al and 5 at. % Ga, and the V element portion is P.

According to another exemplary embodiment, the high aluminum contentIII-V material layer is In_(0.5)Al0_(.5)P, wherein the III elementportion is 50 at. % In and 50 at. % Al, and the V element portion is P.

After the high aluminum content III-V material layer 120 is optionallydeposited on the substrate, the graded layer 130 is formed. For example,GaAs is deposited (without In). The In content is gradually increased,while simultaneously decreasing the Ga content.

To form the graded layer, In must be present in a III-V materialtogether with another III element. As In at. % increases, another IIIelement at. % decreases. The V element portion remains substantiallyconstant.

In another example, the graded layer 130 can be formed by initiallydepositing a substantially pure layer of GaAs and then subsequentlydepositing a layer of In_(0.2)Ga_(0.8)As on top.

The graded layer 130 includes InGaAs or InAlAs with an increasing atomicgradient of In up to 35 at. % (as the III element portion) in the y-axisdirection (see FIG. 1B). In some embodiments, the graded layer 130includes InGaAs or InAlAs with an increasing In atomic gradient fromabout 0 at. % to about 35 at. % in the y-axis direction. Higher atomicgradients (including more than 35 at. % In.) are not used because phaseseparation can occur at higher amounts, which could increase thedislocation density and roughness.

The graded layer 130 includes an In atomic gradient, which can be alinear or step-wise gradient of discrete graded layers. For example, thegraded layer 130 can include a steady linear atomic gradient of In fromabout 0 to about 35 at. %. In other embodiments, the graded layer 130includes a step-wise atomic gradient of In up to 35 wt. %, for example,discrete layers of increasing amounts of In (e.g., 1, 2, 3, 4, 5, 6, 7,8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,26, 27, 28, 29, 30, 31, 32, 33, 34, and 35 at. %). Although, otherstep-wise atomic gradients of larger discrete layers can be used.

The graded buffer is used to form a graded layer 130 having a thicknessin a range from about 100 nm to about 10 μm. In one embodiment, thethickness of the graded layer 130 is in a range from about 0.5 to about1.5 μm. In some embodiments, the thickness of the graded layer 130 isabout or in any range from about 100 nm, 500 nm, 1 μm, 2 μm, 5 μm, 7 μm,and 10 μm.

FIG. 1C illustrates a cross-sectional side view of an InGaAs layer 140disposed on the graded layer 130 of FIG. 1B. The InGaAs layer 140 isstrained and thinner than the graded layer 130 and has a thickness in arange from about 1 nm to about 20 nm. The InGaAs layer 140 forms achannel layer that can be used in transistor devices, for example,planar transistors, high electron mobility transistors (HEMT), or finfield effect transistors (FinFET). In some embodiments, the InGaAs layer140 has a thickness in a range from about 5 nm to about 15 nm. In otherembodiments, the InGaAs layer has a thickness about or in any range fromabout 1, 2, 5, 7, 10, 12, 15, 17, and 20 nm.

FIG. 2 illustrates a cross-sectional side view of a semiconductingmaterial 200 having a partially oxidized high aluminum content materiallayer 120 according to an exemplary embodiment. The high aluminumcontent III-V material layer 120 is oxidized to include one or more AlOportions 210. The high aluminum content III-V material layer 120 withthe AlO portion 210 is formed on the substrate 110. The graded layer 130is formed on the high aluminum content III-V material layer 120 portionsand AlO portions. The InGaAs layer 140 is formed on the graded layer130.

The amount or fraction of the high aluminum content III-V material layer120 that is oxidized to the AlO portion 210 is not intended to belimited. For example, the semiconducting material 200 can include amajority of un-oxidized portions of a majority of AlO. Partiallyoxidizing the high aluminum content III-V material layer 120 can beperformed in any manner such that a portion of the high aluminum contentIII-V material layer 120 includes AlO.

Any oxidation processes can be used. For example, a hydrothermaltreatment, such as wet oxidation, can be used. In wet oxidation, thehigh aluminum content III-V material layer 120 on the substrate 110 issuspended in water (or water vapor) and oxygen is used as the oxidizer.Alternatively, air can be used as the oxidizer (referred to as wet airoxidation (WAO). The water is superheated to a temperature above thenormal boiling point of water (100° C.), but below the critical point(374° C.). During wet oxidation, the system is maintained under pressureto avoid excessive evaporation of water.

In an exemplary embodiment, oxidizing the high aluminum content III-Vmaterial layer 120 includes flowing nitrogen gas and water vapor ontothe high aluminum content III-V material layer 120. Then the highaluminum content III-V material layer 120 is heated to a temperature ina range from about 100 to about 400° Celsius (° C.) to oxidize thematerial to AlO. Because oxidation of the high aluminum content III-Vmaterial layer 120 is faster than GaAs, the high aluminum content III-Vmaterial layer 120 is selectively oxidized.

FIG. 3 illustrates a cross-sectional side view of a semiconductingmaterial 300 having a high aluminum content III-V material layer 120partially oxidized along lateral edges according to an exemplaryembodiment. The AlO portions 310 can be any fraction or portion of thehigh aluminum content III-V material layer 120. The high aluminumcontent III-V material layer 120 with AlO portions 310 are formed on thesubstrate 110. The graded layer 130 is formed on the high aluminumcontent III-V material layer 120 with AlO portions 310. The InGaAs layer140 is formed on the graded layer 130.

FIG. 4 illustrates a cross-sectional side view of a semiconductingmaterial 400 having a high aluminum content III-V material layer 120that is substantially fully oxidized to AlO according to an exemplaryembodiment. When oxidation begins on the lateral edges of the highaluminum content III-V material layer 120, any un-oxidized remainingportion will remain in a central region of the high aluminum contentIII-V material layer 120. The high aluminum content III-V material layer120 with AlO portions 310 are formed on the substrate 110. The gradedlayer 130 is formed on the high aluminum content III-V material layer120 with AlO portions 310. The InGaAs layer 140 is formed on the gradedlayer 130. The high aluminum content III-V material layer 120 can befully oxidized to AlO.

The semiconducting materials 100, 200, 300, and 400 described above havedislocation densities in a range from about 1×10² to about 1×10⁹defects/cm². In some embodiments, the semiconducting materials disclosedherein have dislocation densities in a range from about 1×10⁶ to about1×10⁸ defects/cm². In other embodiments, the semiconducting materialshave defect densities of less than 2×10⁹ defects/cm².

The defect density is determined using a plan-view TEM image under twobeam conditions. Defects include dislocations and stacking faults.

The semiconducting materials disclosed herein are substantially free ofstacking faults. The presence of stacking defaults is determined byanalyzing plan-view TEM images.

The semiconducting materials have an average roughness (RMS) of lessthan 10 nanometers (nm). In some embodiments, the semiconductingmaterials have a RMS of less than 6 nm.

The average roughness, or RMS, is determined by AFM. The AFM instrumentcan provide the roughness RMS value directly. The RMS value (R_(q)) isdetermined using the following equation:

${R_{q} = \sqrt{\frac{1}{n}{\sum\limits_{i = 1}^{n}y_{i}^{2}}}},$

wherein y_(i) is (R_(i)−R_(av)), R_(i) is measured roughness, and R_(av)is the average roughness.

EXAMPLES Example 1

FIG. 5A is a TEM image of a cross-sectional view of a graded layer 520of InGaAs having an increasing In atomic gradient up to 20%. The AlAslayer 510 had a thickness of 0.07 micrometers, the graded layer 520 onthe substrate 510 had a thickness of 1.51 micrometers, and the relaxedInGaAs layer 530 on the graded layer 520 had a thickness of 0.28micrometers. The thin strained InGaAs layer 550 included 44% In. Thedislocation network region 540 showed that substantially no phaseseparation occurred.

FIG. 5B is a TEM image of a cross-sectional view of a graded layer 520of InGaAs having an increasing atomic gradient of In up to 20%. Thegraded layer 520 was formed on the AlAs layer 510, and the thin strainedInGaAs layer 530 was formed on the graded layer 520. The dislocationnetwork region 540 showed that substantially no phase separationoccurred.

Example 2

FIG. 6A is a plan-view TEM image of top view of a InGaAs layer formed ona graded layer as disclosed herein. As shown, the InGaAs layer wassubstantially free of stacking faults. The dislocation density also wasreduced to about 1×10⁷ defects/cm².

FIG. 6B is an AFM image of the InGaAs layer disposed on a siliconsubstrate. The InGaAs layer had an average roughness (RMS) of about 3.12nm.

Example 3

FIG. 7A is a SEM image showing oxidation of the AlAs layer 720 to AlO730. An AlAs layer 720 was formed on a substrate. A GaAs layer 740 wasformed on the AlAs layer 720. Wet oxidation was performed on the AlAslayer by flowing nitrogen gas and water vapor onto the AlAs layer 720.Then high temperature was used to selectively oxidize the AlAs layer 720to AlO 730. Oxidation of AlAs layer 720 to AlO 730 began on the lateraledges of the AlAs layer 720, with the oxidation front 740 moving fromthe edge of the AlAs layer 720 to the central portion of the AlAs layer720.

FIG. 7B is a SEM image showing a substantially fully oxidized AlAslayer. The material includes an AlAs layer 720 that is substantiallyfully oxidized to AlO 730. The AlO layer was formed between two GaAslayers 740.

Example 4

FIG. 8A illustrates linear current (Amperes (A)) as a function ofvoltage (Volts (V)) in semiconducting materials having a partiallyoxidized AlAs layer 820. For comparison, an unoxidized sample 810demonstrated current leakage. Thus, partial oxidation of AlAs to AlOreduced substrate/current leakage.

FIG. 8B illustrates a log scale graph of FIG. 8A. Semiconductingmaterials having partially oxidized 830 and unoxidized 840 AlAs layerswere compared. Curve 840 again showed current leakage when the AlAs wasnot oxidized.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, element components,and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below are intended toinclude any structure, material, or act for performing the function incombination with other claimed elements as specifically claimed. Thedescription of the present invention has been presented for purposes ofillustration and description, but is not intended to be exhaustive orlimited to the invention in the form disclosed. Many modifications andvariations will be apparent to those of ordinary skill in the artwithout departing from the scope and spirit of the invention. Theembodiment was chosen and described in order to best explain theprinciples of the invention and the practical application, and to enableothers of ordinary skill in the art to understand the invention forvarious embodiments with various modifications as are suited to theparticular use contemplated.

The flow diagrams depicted herein are just one example. There may bemany variations to this diagram or the steps (or operations) describedtherein without departing from the spirit of the invention. Forinstance, the steps may be performed in a differing order or steps maybe added, deleted or modified. All of these variations are considered apart of the claimed invention.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Manymodifications and variations will be apparent to those of ordinary skillin the art without departing from the scope and spirit of the describedembodiments. The terminology used herein was chosen to best explain theprinciples of the embodiments, the practical application or technicalimprovement over technologies found in the marketplace, or to enableothers of ordinary skill in the art to understand the embodimentsdisclosed herein.

What is claimed is:
 1. A semiconducting material, comprising: asubstrate; a high aluminum content III-V material layer disposed on thesubstrate, the III-V material layer comprising at least one III elementand a V element, the at leasing one III element comprising Al and beingpresent in an amount of least 50 at. % based on total atomic weight ofthe at least one III element; a graded layer of an In containing III-Vmaterial disposed on the high aluminum content III-V material layer, theIn containing III-V material being InGaAs or InAlAs and comprising In inan increasing atomic gradient up to 35 at. % based on total atomicweight of InGa or InAl; and a InGaAs layer disposed on the graded layer,the InGaAs layer comprising about 25 to about 100 at. % In based ontotal atomic weight of InGa.
 2. The semiconducting material of claim 1,wherein the high aluminum content III-V material layer is partiallyoxidized to include AlO.
 3. The semiconducting material of claim 1,wherein the graded layer has a thickness in a range from about 0.5 toabout 1.5 micrometers.